/*
 * Copyright (c) 2001-2003 Swedish Institute of Computer Science.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
 * OF SUCH DAMAGE.
 *
 * This file is part of the lwIP TCP/IP stack.
 *
 * Author: Adam Dunkels <adam@sics.se>
 *
 * Improved by Marc Boucher <marc@mbsi.ca> and David Haas <dhaas@alum.rpi.edu>
 *
 */

#include "lwip/opt.h"
#include "lwip/api.h"
#include "lwip/arch.h"
#include "lwip/sys.h"

#include "lwip/sockets.h"

#include <intrman.h>
#include <thsemap.h>
#include <sysclib.h>
#include <errno.h>

#include "smsutils.h"

#define NUM_SOCKETS MEMP_NUM_NETCONN

struct lwip_socket
{
    struct netconn *conn;
    struct netbuf *lastdata;
    u16_t lastoffset;
    s16_t rcvevent;
    u16_t sendevent;
    u16_t flags;
    int err;
};

struct lwip_select_cb
{
    struct lwip_select_cb *next;
    fd_set *readset;
    fd_set *writeset;
    fd_set *exceptset;
    int sem_signalled;
    sys_sem_t sem;
};

static struct lwip_socket sockets[NUM_SOCKETS];
static struct lwip_select_cb *select_cb_list = 0;

static sys_sem_t socksem = 0;
static sys_sem_t selectsem = 0;

static void
event_callback(struct netconn *conn, enum netconn_evt evt, u16_t len);

static int err_to_errno_table[11] = {
    0,            /* ERR_OK    0      No error, everything OK. */
    ENOMEM,       /* ERR_MEM  -1      Out of memory error.     */
    ENOBUFS,      /* ERR_BUF  -2      Buffer error.            */
    ECONNABORTED, /* ERR_ABRT -3      Connection aborted.      */
    ECONNRESET,   /* ERR_RST  -4      Connection reset.        */
    ESHUTDOWN,    /* ERR_CLSD -5      Connection closed.       */
    ENOTCONN,     /* ERR_CONN -6      Not connected.           */
    EINVAL,       /* ERR_VAL  -7      Illegal value.           */
    EIO,          /* ERR_ARG  -8      Illegal argument.        */
    EHOSTUNREACH, /* ERR_RTE  -9      Routing problem.         */
    EADDRINUSE    /* ERR_USE  -10     Address in use.          */
};

#define err_to_errno(err)                                  \
    ((err) < (sizeof(err_to_errno_table) / sizeof(int))) ? \
        err_to_errno_table[-(err)] :                       \
        EIO

#ifdef ERRNO
#define set_errno(err) errno = (err)
#else
#define set_errno(err)
#endif

#define sock_set_errno(sk, e) \
    do {                      \
        sk->err = (e);        \
        set_errno(sk->err);   \
    } while (0)


static struct lwip_socket *
get_socket(int s)
{
    struct lwip_socket *sock;

    if ((s < 0) || (s > NUM_SOCKETS)) {
        LWIP_DEBUGF(SOCKETS_DEBUG, ("get_socket(%d): invalid\n", s));
        set_errno(EBADF);
        return NULL;
    }

    sock = &sockets[s];

    if (!sock->conn) {
        LWIP_DEBUGF(SOCKETS_DEBUG, ("get_socket(%d): not active\n", s));
        set_errno(EBADF);
        return NULL;
    }

    return sock;
}

static int
alloc_socket(struct netconn *newconn)
{
    int i;

    if (!socksem)
        socksem = sys_sem_new(1);

    /* Protect socket array */
    sys_sem_wait(socksem);

    /* allocate a new socket identifier */
    for (i = 0; i < NUM_SOCKETS; ++i) {
        if (!sockets[i].conn) {
            sockets[i].conn = newconn;
            sockets[i].lastdata = NULL;
            sockets[i].lastoffset = 0;
            sockets[i].rcvevent = 0;
            sockets[i].sendevent = 1; /* TCP send buf is empty */
            sockets[i].flags = 0;
            sockets[i].err = 0;
            sys_sem_signal(socksem);
            return i;
        }
    }
    sys_sem_signal(socksem);
    return -1;
}

int lwip_accept(int s, struct sockaddr *addr, socklen_t *addrlen)
{
    struct lwip_socket *sock;
    struct netconn *newconn;
    struct ip_addr naddr;
    u16_t port;
    int newsock;
    struct sockaddr_in sin;

    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_accept(%d)...\n", s));
    sock = get_socket(s);
    if (!sock) {
        set_errno(EBADF);
        return -1;
    }

    newconn = netconn_accept(sock->conn);

    /* get the IP address and port of the remote host */
    netconn_peer(newconn, &naddr, &port);

    mips_memset(&sin, 0, sizeof(sin));
    sin.sin_len = sizeof(sin);
    sin.sin_family = AF_INET;
    sin.sin_port = htons(port);
    sin.sin_addr.s_addr = naddr.addr;

    if (*addrlen > sizeof(sin))
        *addrlen = sizeof(sin);

    mips_memcpy(addr, &sin, *addrlen);

    newsock = alloc_socket(newconn);
    if (newsock == -1) {
        netconn_delete(newconn);
        sock_set_errno(sock, ENOBUFS);
        return -1;
    }
    newconn->callback = event_callback;
    sock = get_socket(newsock);

    sys_sem_wait(socksem);
    sock->rcvevent += -1 - newconn->socket;
    newconn->socket = newsock;
    sys_sem_signal(socksem);

    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_accept(%d) returning new sock=%d addr=", s, newsock));
    ip_addr_debug_print(SOCKETS_DEBUG, &naddr);
    LWIP_DEBUGF(SOCKETS_DEBUG, (" port=%u\n", port));

    sock_set_errno(sock, 0);
    return newsock;
}

int lwip_bind(int s, struct sockaddr *name, socklen_t namelen)
{
    struct lwip_socket *sock;
    struct ip_addr local_addr;
    u16_t local_port;
    err_t err;

    sock = get_socket(s);
    if (!sock) {
        set_errno(EBADF);
        return -1;
    }

    local_addr.addr = ((struct sockaddr_in *)name)->sin_addr.s_addr;
    local_port = ((struct sockaddr_in *)name)->sin_port;

    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_bind(%d, addr=", s));
    ip_addr_debug_print(SOCKETS_DEBUG, &local_addr);
    LWIP_DEBUGF(SOCKETS_DEBUG, (" port=%u)\n", ntohs(local_port)));

    err = netconn_bind(sock->conn, &local_addr, ntohs(local_port));

    if (err != ERR_OK) {
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_bind(%d) failed, err=%d\n", s, err));
        sock_set_errno(sock, err_to_errno(err));
        return -1;
    }

    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_bind(%d) succeeded\n", s));
    sock_set_errno(sock, 0);
    return 0;
}

int lwip_close(int s)
{
    struct lwip_socket *sock;

    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_close(%d)\n", s));
    if (!socksem)
        socksem = sys_sem_new(1);

    /* We cannot allow multiple closes of the same socket. */
    sys_sem_wait(socksem);

    sock = get_socket(s);
    if (!sock) {
        sys_sem_signal(socksem);
        set_errno(EBADF);
        return -1;
    }

    netconn_delete(sock->conn);
    if (sock->lastdata) {
        netbuf_delete(sock->lastdata);
    }
    sock->lastdata = NULL;
    sock->lastoffset = 0;
    sock->conn = NULL;
    sys_sem_signal(socksem);
    sock_set_errno(sock, 0);
    return 0;
}

int lwip_connect(int s, struct sockaddr *name, socklen_t namelen)
{
    struct lwip_socket *sock;
    err_t err;

    sock = get_socket(s);
    if (!sock) {
        set_errno(EBADF);
        return -1;
    }

    if (((struct sockaddr_in *)name)->sin_family == AF_UNSPEC) {
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_connect(%d, AF_UNSPEC)\n", s));
        err = netconn_disconnect(sock->conn);
    } else {
        struct ip_addr remote_addr;
        u16_t remote_port;

        remote_addr.addr = ((struct sockaddr_in *)name)->sin_addr.s_addr;
        remote_port = ((struct sockaddr_in *)name)->sin_port;

        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_connect(%d, addr=", s));
        ip_addr_debug_print(SOCKETS_DEBUG, &remote_addr);
        LWIP_DEBUGF(SOCKETS_DEBUG, (" port=%u)\n", ntohs(remote_port)));

        err = netconn_connect(sock->conn, &remote_addr, ntohs(remote_port));
    }

    if (err != ERR_OK) {
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_connect(%d) failed, err=%d\n", s, err));
        sock_set_errno(sock, err_to_errno(err));
        return -1;
    }

    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_connect(%d) succeeded\n", s));
    sock_set_errno(sock, 0);
    return 0;
}

int lwip_listen(int s, int backlog)
{
    struct lwip_socket *sock;
    err_t err;

    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_listen(%d, backlog=%d)\n", s, backlog));
    sock = get_socket(s);
    if (!sock) {
        set_errno(EBADF);
        return -1;
    }

    err = netconn_listen(sock->conn);

    if (err != ERR_OK) {
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_listen(%d) failed, err=%d\n", s, err));
        sock_set_errno(sock, err_to_errno(err));
        return -1;
    }

    sock_set_errno(sock, 0);
    return 0;
}

// Note: This function was modified so that the SMB header can be retrieved directly and the payload stored separately from it.
int lwip_recvfrom(int s, void *header, int index, void *payload, int plen, unsigned int flags,
                  struct sockaddr *from, socklen_t *fromlen)
{
    struct lwip_socket *sock;
    struct netbuf *buf;
    u16_t avail_len, copylen = 0;
    struct ip_addr *addr;
    u16_t port;


    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_recvfrom(%d, %p, %d, 0x%x, ..)\n", s, payload, plen, flags));
    sock = get_socket(s);
    if (!sock) {
        set_errno(EBADF);
        return -1;
    }

    /* Check if there is data left from the last recv operation. */
    if (sock->lastdata) {
        buf = sock->lastdata;
    } else {
        /* If this is non-blocking call, then check first */
        if (((flags & MSG_DONTWAIT) || (sock->flags & O_NONBLOCK)) && (sock->rcvevent <= 0)) {
            LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_recvfrom(%d): returning EWOULDBLOCK\n", s));
            sock_set_errno(sock, EWOULDBLOCK);
            return -1;
        }

        /* No data was left from the previous operation, so we try to get
       some from the network. */
        buf = netconn_recv(sock->conn);

        if (!buf) {
            /* We should really do some error checking here. */
            LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_recvfrom(%d): buf == NULL!\n", s));
            sock_set_errno(sock, 0);
            return 0;
        }
    }

    avail_len = netbuf_len(buf);

    avail_len -= sock->lastoffset;

    /* copy the contents of the received buffer into
     the supplied memory pointer mem */
    if (index) {
        if (avail_len >= 63) { // header of (SMB command) READ ANDX RESPONSE is 63 + padding bytes, which are "0x00" thus useless
            netbuf_copy_partial(buf, header, 63, sock->lastoffset);
            index = ((u8_t *)header)[index] + 4; // The word at offset 0 is sessionHeader, which Microsoft doesn't consider as being part of the SMB header.
            copylen = index;
            avail_len -= index;
        } else {
            netbuf_copy_partial(buf, header, avail_len, sock->lastoffset);
            copylen = avail_len;
            avail_len = 0;
        }
    }

    if (avail_len) {
        if (plen > avail_len)
            plen = avail_len;

        netbuf_copy_partial(buf, payload, plen, sock->lastoffset + index);
        copylen += plen;
        avail_len -= plen;
    }

    /* Check to see from where the data was. */
    if (from && fromlen) {
        struct sockaddr_in sin;

        addr = netbuf_fromaddr(buf);
        port = netbuf_fromport(buf);

        mips_memset(&sin, 0, sizeof(sin));
        sin.sin_len = sizeof(sin);
        sin.sin_family = AF_INET;
        sin.sin_port = htons(port);
        sin.sin_addr.s_addr = addr->addr;

        if (*fromlen > sizeof(sin))
            *fromlen = sizeof(sin);

        mips_memcpy(from, &sin, *fromlen);

        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_recvfrom(%d): addr=", s));
        ip_addr_debug_print(SOCKETS_DEBUG, addr);
        LWIP_DEBUGF(SOCKETS_DEBUG, (" port=%u len=%u\n", port, copylen));
    } else {
#if SOCKETS_DEBUG > 0
        addr = netbuf_fromaddr(buf);
        port = netbuf_fromport(buf);

        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_recvfrom(%d): addr=", s));
        ip_addr_debug_print(SOCKETS_DEBUG, addr);
        LWIP_DEBUGF(SOCKETS_DEBUG, (" port=%u len=%u\n", port, copylen));
#endif
    }

    /* If this is a TCP socket, check if there is data left in the
     buffer. If so, it should be saved in the sock structure for next
     time around. */
    if (netconn_type(sock->conn) == NETCONN_TCP && avail_len > 0) {
        sock->lastdata = buf;
        sock->lastoffset += copylen;
    } else {
        sock->lastdata = NULL;
        sock->lastoffset = 0;
        netbuf_delete(buf);
    }

    sock_set_errno(sock, 0);
    return copylen;
}

#ifdef FULL_LWIP
int lwip_read(int s, void *mem, int len)
{
    return lwip_recvfrom(s, NULL, 0, mem, len, 0, NULL, NULL);
}
#endif

int lwip_recv(int s, void *mem, int len, unsigned int flags)
{
    return lwip_recvfrom(s, NULL, 0, mem, len, flags, NULL, NULL);
}

int lwip_send(int s, void *data, int size, unsigned int flags)
{
    struct lwip_socket *sock;
    struct netbuf *buf;
    err_t err;

    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_send(%d, data=%p, size=%d, flags=0x%x)\n", s, data, size, flags));

    sock = get_socket(s);
    if (!sock) {
        set_errno(EBADF);
        return -1;
    }

    switch (netconn_type(sock->conn)) {
        case NETCONN_RAW:
        case NETCONN_UDP:
        case NETCONN_UDPLITE:
        case NETCONN_UDPNOCHKSUM:
            /* create a buffer */
            buf = netbuf_new();

            if (!buf) {
                LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_send(%d) ENOBUFS\n", s));
                sock_set_errno(sock, ENOBUFS);
                return -1;
            }

            /* make the buffer point to the data that should
       be sent */
            if ((err = netbuf_ref(buf, data, size)) == ERR_OK) {
                /* send the data */
                err = netconn_send(sock->conn, buf);
            }

            /* deallocated the buffer */
            netbuf_delete(buf);
            break;
        case NETCONN_TCP:
            err = netconn_write(sock->conn, data, size, NETCONN_COPY);
            break;
        default:
            err = ERR_ARG;
            break;
    }
    if (err != ERR_OK) {
        LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_send(%d) err=%d\n", s, err));
        sock_set_errno(sock, err_to_errno(err));
        return -1;
    }

    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_send(%d) ok size=%d\n", s, size));
    sock_set_errno(sock, 0);
    return size;
}

int lwip_sendto(int s, void *data, int size, unsigned int flags,
                struct sockaddr *to, socklen_t tolen)
{
    struct lwip_socket *sock;
    struct ip_addr remote_addr, addr;
    u16_t remote_port, port;
    int ret, connected;

    sock = get_socket(s);
    if (!sock) {
        set_errno(EBADF);
        return -1;
    }

    /* get the peer if currently connected */
    connected = (netconn_peer(sock->conn, &addr, &port) == ERR_OK);

    remote_addr.addr = ((struct sockaddr_in *)to)->sin_addr.s_addr;
    remote_port = ((struct sockaddr_in *)to)->sin_port;

    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_sendto(%d, data=%p, size=%d, flags=0x%x to=", s, data, size, flags));
    ip_addr_debug_print(SOCKETS_DEBUG, &remote_addr);
    LWIP_DEBUGF(SOCKETS_DEBUG, (" port=%u\n", ntohs(remote_port)));

    netconn_connect(sock->conn, &remote_addr, ntohs(remote_port));

    ret = lwip_send(s, data, size, flags);

    /* reset the remote address and port number
     of the connection */
    if (connected)
        netconn_connect(sock->conn, &addr, port);
    else
        netconn_disconnect(sock->conn);
    return ret;
}

int lwip_socket(int domain, int type, int protocol)
{
    struct netconn *conn;
    int i;

    /* create a netconn */
    switch (type) {
        case SOCK_RAW:
            conn = netconn_new_with_proto_and_callback(NETCONN_RAW, protocol, event_callback);
            LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_socket(%s, SOCK_RAW, %d) = ", domain == PF_INET ? "PF_INET" : "UNKNOWN", protocol));
            break;
        case SOCK_DGRAM:
            conn = netconn_new_with_callback(NETCONN_UDP, event_callback);
            LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_socket(%s, SOCK_DGRAM, %d) = ", domain == PF_INET ? "PF_INET" : "UNKNOWN", protocol));
            break;
        case SOCK_STREAM:
            conn = netconn_new_with_callback(NETCONN_TCP, event_callback);
            LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_socket(%s, SOCK_STREAM, %d) = ", domain == PF_INET ? "PF_INET" : "UNKNOWN", protocol));
            break;
        default:
            LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_socket(%d, %d/UNKNOWN, %d) = -1\n", domain, type, protocol));
            set_errno(EINVAL);
            return -1;
    }

    if (!conn) {
        LWIP_DEBUGF(SOCKETS_DEBUG, ("-1 / ENOBUFS (could not create netconn)\n"));
        set_errno(ENOBUFS);
        return -1;
    }

    i = alloc_socket(conn);

    if (i == -1) {
        netconn_delete(conn);
        set_errno(ENOBUFS);
        return -1;
    }
    conn->socket = i;
    LWIP_DEBUGF(SOCKETS_DEBUG, ("%d\n", i));
    set_errno(0);
    return i;
}

#ifdef FULL_LWIP
int lwip_write(int s, void *data, int size)
{
    return lwip_send(s, data, size, 0);
}
#endif

#ifdef FULL_LWIP
static int
lwip_selscan(int maxfdp1, fd_set *readset, fd_set *writeset, fd_set *exceptset)
{
    int i, nready = 0;
    fd_set lreadset, lwriteset, lexceptset;
    struct lwip_socket *p_sock;

    FD_ZERO(&lreadset);
    FD_ZERO(&lwriteset);
    FD_ZERO(&lexceptset);

    /* Go through each socket in each list to count number of sockets which
       currently match */
    for (i = 0; i < maxfdp1; i++) {
        if (FD_ISSET(i, readset)) {
            /* See if netconn of this socket is ready for read */
            p_sock = get_socket(i);
            if (p_sock && (p_sock->lastdata || (p_sock->rcvevent > 0))) {
                FD_SET(i, &lreadset);
                LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_selscan: fd=%d ready for reading\n", i));
                nready++;
            }
        }
        if (FD_ISSET(i, writeset)) {
            /* See if netconn of this socket is ready for write */
            p_sock = get_socket(i);
            if (p_sock && p_sock->sendevent) {
                FD_SET(i, &lwriteset);
                LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_selscan: fd=%d ready for writing\n", i));
                nready++;
            }
        }
    }
    *readset = lreadset;
    *writeset = lwriteset;
    FD_ZERO(exceptset);

    return nready;
}

int lwip_select(int maxfdp1, fd_set *readset, fd_set *writeset, fd_set *exceptset,
                struct timeval *timeout)
{
    int i;
    int nready;
    fd_set lreadset, lwriteset, lexceptset;
    u32_t msectimeout;
    struct lwip_select_cb select_cb;
    struct lwip_select_cb *p_selcb;

    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_select(%d, %p, %p, %p, tvsec=%ld tvusec=%ld)\n", maxfdp1, (void *)readset, (void *)writeset, (void *)exceptset, timeout ? timeout->tv_sec : -1L, timeout ? timeout->tv_usec : -1L));

    select_cb.next = 0;
    select_cb.readset = readset;
    select_cb.writeset = writeset;
    select_cb.exceptset = exceptset;
    select_cb.sem_signalled = 0;

    /* Protect ourselves searching through the list */
    if (!selectsem)
        selectsem = sys_sem_new(1);
    sys_sem_wait(selectsem);

    if (readset)
        lreadset = *readset;
    else
        FD_ZERO(&lreadset);
    if (writeset)
        lwriteset = *writeset;
    else
        FD_ZERO(&lwriteset);
    if (exceptset)
        lexceptset = *exceptset;
    else
        FD_ZERO(&lexceptset);

    /* Go through each socket in each list to count number of sockets which
       currently match */
    nready = lwip_selscan(maxfdp1, &lreadset, &lwriteset, &lexceptset);

    /* If we don't have any current events, then suspend if we are supposed to */
    if (!nready) {
        if (timeout && timeout->tv_sec == 0 && timeout->tv_usec == 0) {
            sys_sem_signal(selectsem);
            if (readset)
                FD_ZERO(readset);
            if (writeset)
                FD_ZERO(writeset);
            if (exceptset)
                FD_ZERO(exceptset);

            LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_select: no timeout, returning 0\n"));
            set_errno(0);

            return 0;
        }

        /* add our semaphore to list */
        /* We don't actually need any dynamic memory. Our entry on the
         * list is only valid while we are in this function, so it's ok
         * to use local variables */

        select_cb.sem = sys_sem_new(0);
        /* Note that we are still protected */
        /* Put this select_cb on top of list */
        select_cb.next = select_cb_list;
        select_cb_list = &select_cb;

        /* Now we can safely unprotect */
        sys_sem_signal(selectsem);

        /* Now just wait to be woken */
        if (timeout == 0)
            /* Wait forever */
            msectimeout = 0;
        else
            msectimeout = ((timeout->tv_sec * 1000) + ((timeout->tv_usec + 500) / 1000));

        i = sys_sem_wait_timeout(select_cb.sem, msectimeout);

        /* Take us off the list */
        sys_sem_wait(selectsem);
        if (select_cb_list == &select_cb)
            select_cb_list = select_cb.next;
        else
            for (p_selcb = select_cb_list; p_selcb; p_selcb = p_selcb->next)
                if (p_selcb->next == &select_cb) {
                    p_selcb->next = select_cb.next;
                    break;
                }

        sys_sem_signal(selectsem);

        sys_sem_free(select_cb.sem);
        if (i == SYS_ARCH_TIMEOUT) /* Timeout */
        {
            if (readset)
                FD_ZERO(readset);
            if (writeset)
                FD_ZERO(writeset);
            if (exceptset)
                FD_ZERO(exceptset);

            LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_select: timeout expired\n"));
            set_errno(0);

            return 0;
        }

        if (readset)
            lreadset = *readset;
        else
            FD_ZERO(&lreadset);
        if (writeset)
            lwriteset = *writeset;
        else
            FD_ZERO(&lwriteset);
        if (exceptset)
            lexceptset = *exceptset;
        else
            FD_ZERO(&lexceptset);

        /* See what's set */
        nready = lwip_selscan(maxfdp1, &lreadset, &lwriteset, &lexceptset);
    } else
        sys_sem_signal(selectsem);

    if (readset)
        *readset = lreadset;
    if (writeset)
        *writeset = lwriteset;
    if (exceptset)
        *exceptset = lexceptset;

    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_select: nready=%d\n", nready));
    set_errno(0);

    return nready;
}
#endif

static void
event_callback(struct netconn *conn, enum netconn_evt evt, u16_t len)
{
    int s;
    struct lwip_socket *sock;
    struct lwip_select_cb *scb;

    /* Get socket */
    if (conn) {
        s = conn->socket;
        if (s < 0) {
            /* Data comes in right away after an accept, even though
             * the server task might not have created a new socket yet.
             * Just count down (or up) if that's the case and we
             * will use the data later. Note that only receive events
             * can happen before the new socket is set up. */
            if (evt == NETCONN_EVT_RCVPLUS)
                conn->socket--;
            return;
        }

        sock = get_socket(s);
        if (!sock)
            return;
    } else
        return;

    if (!selectsem)
        selectsem = sys_sem_new(1);

    sys_sem_wait(selectsem);
    /* Set event as required */
    switch (evt) {
        case NETCONN_EVT_RCVPLUS:
            sock->rcvevent++;
            break;
        case NETCONN_EVT_RCVMINUS:
            sock->rcvevent--;
            break;
        case NETCONN_EVT_SENDPLUS:
            sock->sendevent = 1;
            break;
        case NETCONN_EVT_SENDMINUS:
            sock->sendevent = 0;
            break;
    }
    sys_sem_signal(selectsem);

    /* Now decide if anyone is waiting for this socket */
    /* NOTE: This code is written this way to protect the select link list
       but to avoid a deadlock situation by releasing socksem before
       signalling for the select. This means we need to go through the list
       multiple times ONLY IF a select was actually waiting. We go through
       the list the number of waiting select calls + 1. This list is
       expected to be small. */
    while (1) {
        sys_sem_wait(selectsem);
        for (scb = select_cb_list; scb; scb = scb->next) {
            if (scb->sem_signalled == 0) {
                /* Test this select call for our socket */
                if (scb->readset && FD_ISSET(s, scb->readset))
                    if (sock->rcvevent > 0)
                        break;
                if (scb->writeset && FD_ISSET(s, scb->writeset))
                    if (sock->sendevent)
                        break;
            }
        }
        if (scb) {
            scb->sem_signalled = 1;
            sys_sem_signal(scb->sem);
            sys_sem_signal(selectsem);
        } else {
            sys_sem_signal(selectsem);
            break;
        }
    }
}



int lwip_shutdown(int s, int how)
{
    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_shutdown(%d, how=%d)\n", s, how));
    return lwip_close(s); /* XXX temporary hack until proper implementation */
}

#ifdef FULL_LWIP
int lwip_getpeername(int s, struct sockaddr *name, socklen_t *namelen)
{
    struct lwip_socket *sock;
    struct sockaddr_in sin;
    struct ip_addr naddr;

    sock = get_socket(s);
    if (!sock) {
        set_errno(EBADF);
        return -1;
    }

    mips_memset(&sin, 0, sizeof(sin));
    sin.sin_len = sizeof(sin);
    sin.sin_family = AF_INET;

    /* get the IP address and port of the remote host */
    netconn_peer(sock->conn, &naddr, &sin.sin_port);

    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getpeername(%d, addr=", s));
    ip_addr_debug_print(SOCKETS_DEBUG, &naddr);
    LWIP_DEBUGF(SOCKETS_DEBUG, (" port=%d)\n", sin.sin_port));

    sin.sin_port = htons(sin.sin_port);
    sin.sin_addr.s_addr = naddr.addr;

    if (*namelen > sizeof(sin))
        *namelen = sizeof(sin);

    mips_memcpy(name, &sin, *namelen);
    sock_set_errno(sock, 0);
    return 0;
}

int lwip_getsockname(int s, struct sockaddr *name, socklen_t *namelen)
{
    struct lwip_socket *sock;
    struct sockaddr_in sin;
    struct ip_addr *naddr;

    sock = get_socket(s);
    if (!sock) {
        set_errno(EBADF);
        return -1;
    }

    mips_memset(&sin, 0, sizeof(sin));
    sin.sin_len = sizeof(sin);
    sin.sin_family = AF_INET;

    /* get the IP address and port of the remote host */
    netconn_addr(sock->conn, &naddr, &sin.sin_port);

    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockname(%d, addr=", s));
    ip_addr_debug_print(SOCKETS_DEBUG, naddr);
    LWIP_DEBUGF(SOCKETS_DEBUG, (" port=%d)\n", sin.sin_port));

    sin.sin_port = htons(sin.sin_port);
    sin.sin_addr.s_addr = naddr->addr;

    if (*namelen > sizeof(sin))
        *namelen = sizeof(sin);

    mips_memcpy(name, &sin, *namelen);
    sock_set_errno(sock, 0);
    return 0;
}

int lwip_getsockopt(int s, int level, int optname, void *optval, socklen_t *optlen)
{
    int err = 0;
    struct lwip_socket *sock = get_socket(s);

    if (!sock) {
        set_errno(EBADF);
        return -1;
    }

    if (NULL == optval || NULL == optlen) {
        sock_set_errno(sock, EFAULT);
        return -1;
    }

    /* Do length and type checks for the various options first, to keep it readable. */
    switch (level) {

        /* Level: SOL_SOCKET */
        case SOL_SOCKET:
            switch (optname) {

                case SO_ACCEPTCONN:
                case SO_BROADCAST:
                /* UNIMPL case SO_DEBUG: */
                /* UNIMPL case SO_DONTROUTE: */
                case SO_ERROR:
                case SO_KEEPALIVE:
/* UNIMPL case SO_OOBINLINE: */
/* UNIMPL case SO_RCVBUF: */
/* UNIMPL case SO_SNDBUF: */
/* UNIMPL case SO_RCVLOWAT: */
/* UNIMPL case SO_SNDLOWAT: */
#ifdef SO_REUSE
                case SO_REUSEADDR:
                case SO_REUSEPORT:
#endif /* SO_REUSE */
                case SO_TYPE:
                    /* UNIMPL case SO_USELOOPBACK: */
                    if (*optlen < sizeof(int)) {
                        err = EINVAL;
                    }
                    break;

                default:
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, SOL_SOCKET, UNIMPL: optname=0x%x, ..)\n", s, optname));
                    err = ENOPROTOOPT;
            } /* switch */
            break;

        /* Level: IPPROTO_IP */
        case IPPROTO_IP:
            switch (optname) {
                /* UNIMPL case IP_HDRINCL: */
                /* UNIMPL case IP_RCVDSTADDR: */
                /* UNIMPL case IP_RCVIF: */
                case IP_TTL:
                case IP_TOS:
                    if (*optlen < sizeof(int)) {
                        err = EINVAL;
                    }
                    break;

                default:
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, IPPROTO_IP, UNIMPL: optname=0x%x, ..)\n", s, optname));
                    err = ENOPROTOOPT;
            } /* switch */
            break;

        /* Level: IPPROTO_TCP */
        case IPPROTO_TCP:
            if (*optlen < sizeof(int)) {
                err = EINVAL;
                break;
            }

            /* If this is no TCP socket, ignore any options. */
            if (sock->conn->type != NETCONN_TCP)
                return 0;

            switch (optname) {
                case TCP_NODELAY:
                case TCP_KEEPALIVE:
                case TCP_ACKNODELAY:
                case TCP_EVENSEG:
                    break;

                default:
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, IPPROTO_TCP, UNIMPL: optname=0x%x, ..)\n", s, optname));
                    err = ENOPROTOOPT;
            } /* switch */
            break;

        /* UNDEFINED LEVEL */
        default:
            LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, level=0x%x, UNIMPL: optname=0x%x, ..)\n", s, level, optname));
            err = ENOPROTOOPT;
    } /* switch */


    if (0 != err) {
        sock_set_errno(sock, err);
        return -1;
    }



    /* Now do the actual option processing */

    switch (level) {

        /* Level: SOL_SOCKET */
        case SOL_SOCKET:
            switch (optname) {

                /* The option flags */
                case SO_ACCEPTCONN:
                case SO_BROADCAST:
                /* UNIMPL case SO_DEBUG: */
                /* UNIMPL case SO_DONTROUTE: */
                case SO_KEEPALIVE:
/* UNIMPL case SO_OOBINCLUDE: */
#ifdef SO_REUSE
                case SO_REUSEADDR:
                case SO_REUSEPORT:
#endif /* SO_REUSE */
                    /*case SO_USELOOPBACK: UNIMPL */
                    *(int *)optval = sock->conn->pcb.tcp->so_options & optname;
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, SOL_SOCKET, optname=0x%x, ..) = %s\n", s, optname, (*(int *)optval ? "on" : "off")));
                    break;

                case SO_TYPE:
                    switch (sock->conn->type) {
                        case NETCONN_RAW:
                            *(int *)optval = SOCK_RAW;
                            break;
                        case NETCONN_TCP:
                            *(int *)optval = SOCK_STREAM;
                            break;
                        case NETCONN_UDP:
                        case NETCONN_UDPLITE:
                        case NETCONN_UDPNOCHKSUM:
                            *(int *)optval = SOCK_DGRAM;
                            break;
                        default: /* unrecognized socket type */
                            *(int *)optval = sock->conn->type;
                            LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, SOL_SOCKET, SO_TYPE): unrecognized socket type %d\n", s, *(int *)optval));
                    } /* switch */
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, SOL_SOCKET, SO_TYPE) = %d\n", s, *(int *)optval));
                    break;

                case SO_ERROR:
                    *(int *)optval = sock->err;
                    sock->err = 0;
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, SOL_SOCKET, SO_ERROR) = %d\n", s, *(int *)optval));
                    break;
            } /* switch */
            break;

        /* Level: IPPROTO_IP */
        case IPPROTO_IP:
            switch (optname) {
                case IP_TTL:
                    *(int *)optval = sock->conn->pcb.tcp->ttl;
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, IPPROTO_IP, IP_TTL) = %d\n", s, *(int *)optval));
                    break;
                case IP_TOS:
                    *(int *)optval = sock->conn->pcb.tcp->tos;
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, IPPROTO_IP, IP_TOS) = %d\n", s, *(int *)optval));
                    break;
            } /* switch */
            break;

        /* Level: IPPROTO_TCP */
        case IPPROTO_TCP:
            switch (optname) {
                case TCP_NODELAY:
                    *(int *)optval = (sock->conn->pcb.tcp->flags & TF_NODELAY);
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, IPPROTO_TCP, TCP_NODELAY) = %s\n", s, (*(int *)optval) ? "on" : "off"));
                    break;
                case TCP_KEEPALIVE:
                    *(int *)optval = sock->conn->pcb.tcp->keepalive;
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, IPPROTO_IP, TCP_KEEPALIVE) = %d\n", s, *(int *)optval));
                    break;
                case TCP_ACKNODELAY:
                    *(int *)optval = sock->conn->pcb.tcp->flags & TF_ACKNODELAY;
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, IPPROTO_IP, TCP_ACKNODELAY) = %s\n", s, (*(int *)optval) ? "on" : "off"));
                    break;
                case TCP_EVENSEG:
                    *(int *)optval = sock->conn->pcb.tcp->flags & TF_EVENSEG;
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_getsockopt(%d, IPPROTO_IP, TCP_EVENSEG) = %s\n", s, (*(int *)optval) ? "on" : "off"));
                    break;
            } /* switch */
            break;
    }


    sock_set_errno(sock, err);
    return err ? -1 : 0;
}
#endif

int lwip_setsockopt(int s, int level, int optname, const void *optval, socklen_t optlen)
{
    struct lwip_socket *sock = get_socket(s);
    int err = 0;

    if (!sock) {
        set_errno(EBADF);
        return -1;
    }

    if (NULL == optval) {
        sock_set_errno(sock, EFAULT);
        return -1;
    }


    /* Do length and type checks for the various options first, to keep it readable. */
    switch (level) {

        /* Level: SOL_SOCKET */
        case SOL_SOCKET:
            switch (optname) {

                case SO_BROADCAST:
                /* UNIMPL case SO_DEBUG: */
                /* UNIMPL case SO_DONTROUTE: */
                case SO_KEEPALIVE:
/* UNIMPL case SO_OOBINLINE: */
/* UNIMPL case SO_RCVBUF: */
/* UNIMPL case SO_SNDBUF: */
/* UNIMPL case SO_RCVLOWAT: */
/* UNIMPL case SO_SNDLOWAT: */
#ifdef SO_REUSE
                case SO_REUSEADDR:
                case SO_REUSEPORT:
#endif /* SO_REUSE */
                    /* UNIMPL case SO_USELOOPBACK: */
                    if (optlen < sizeof(int)) {
                        err = EINVAL;
                    }
                    break;
                default:
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, SOL_SOCKET, UNIMPL: optname=0x%x, ..)\n", s, optname));
                    err = ENOPROTOOPT;
            } /* switch */
            break;

        /* Level: IPPROTO_IP */
        case IPPROTO_IP:
            switch (optname) {
                /* UNIMPL case IP_HDRINCL: */
                /* UNIMPL case IP_RCVDSTADDR: */
                /* UNIMPL case IP_RCVIF: */
                case IP_TTL:
                case IP_TOS:
                    if (optlen < sizeof(int)) {
                        err = EINVAL;
                    }
                    break;
                default:
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, IPPROTO_IP, UNIMPL: optname=0x%x, ..)\n", s, optname));
                    err = ENOPROTOOPT;
            } /* switch */
            break;

        /* Level: IPPROTO_TCP */
        case IPPROTO_TCP:
            if (optlen < sizeof(int)) {
                err = EINVAL;
                break;
            }

            /* If this is no TCP socket, ignore any options. */
            if (sock->conn->type != NETCONN_TCP)
                return 0;

            switch (optname) {
                case TCP_NODELAY:
                case TCP_KEEPALIVE:
                case TCP_ACKNODELAY:
                case TCP_EVENSEG:
                    break;

                default:
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, IPPROTO_TCP, UNIMPL: optname=0x%x, ..)\n", s, optname));
                    err = ENOPROTOOPT;
            } /* switch */
            break;

        /* UNDEFINED LEVEL */
        default:
            LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, level=0x%x, UNIMPL: optname=0x%x, ..)\n", s, level, optname));
            err = ENOPROTOOPT;
    } /* switch */


    if (0 != err) {
        sock_set_errno(sock, err);
        return -1;
    }



    /* Now do the actual option processing */

    switch (level) {

        /* Level: SOL_SOCKET */
        case SOL_SOCKET:
            switch (optname) {

                /* The option flags */
                case SO_BROADCAST:
                /* UNIMPL case SO_DEBUG: */
                /* UNIMPL case SO_DONTROUTE: */
                case SO_KEEPALIVE:
/* UNIMPL case SO_OOBINCLUDE: */
#ifdef SO_REUSE
                case SO_REUSEADDR:
                case SO_REUSEPORT:
#endif /* SO_REUSE */
                    /* UNIMPL case SO_USELOOPBACK: */
                    if (*(int *)optval) {
                        sock->conn->pcb.tcp->so_options |= optname;
                    } else {
                        sock->conn->pcb.tcp->so_options &= ~optname;
                    }
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, SOL_SOCKET, optname=0x%x, ..) -> %s\n", s, optname, (*(int *)optval ? "on" : "off")));
                    break;
            } /* switch */
            break;

        /* Level: IPPROTO_IP */
        case IPPROTO_IP:
            switch (optname) {
                case IP_TTL:
                    sock->conn->pcb.tcp->ttl = (u8_t)(*(int *)optval);
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, IPPROTO_IP, IP_TTL, ..) -> %u\n", s, sock->conn->pcb.tcp->ttl));
                    break;
                case IP_TOS:
                    sock->conn->pcb.tcp->tos = (u8_t)(*(int *)optval);
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, IPPROTO_IP, IP_TOS, ..)-> %u\n", s, sock->conn->pcb.tcp->tos));
                    break;
            } /* switch */
            break;

        /* Level: IPPROTO_TCP */
        case IPPROTO_TCP:
            switch (optname) {
                case TCP_NODELAY:
                    if (*(int *)optval) {
                        sock->conn->pcb.tcp->flags |= TF_NODELAY;
                    } else {
                        sock->conn->pcb.tcp->flags &= ~TF_NODELAY;
                    }
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, IPPROTO_TCP, TCP_NODELAY) -> %s\n", s, (*(int *)optval) ? "on" : "off"));
                    break;
                case TCP_KEEPALIVE:
                    sock->conn->pcb.tcp->keepalive = (u32_t)(*(int *)optval);
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, IPPROTO_TCP, TCP_KEEPALIVE) -> %u\n", s, sock->conn->pcb.tcp->keepalive));
                    break;
                case TCP_ACKNODELAY:
                    if (*(int *)optval) {
                        sock->conn->pcb.tcp->flags |= TF_ACKNODELAY;
                    } else {
                        sock->conn->pcb.tcp->flags &= ~TF_ACKNODELAY;
                    }
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, IPPROTO_TCP, TCP_ACKNODELAY) -> %s\n", s, (*(int *)optval) ? "on" : "off"));
                    break;
                case TCP_EVENSEG:
                    if (*(int *)optval) {
                        sock->conn->pcb.tcp->flags |= TF_EVENSEG;
                    } else {
                        sock->conn->pcb.tcp->flags &= ~TF_EVENSEG;
                    }
                    LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_setsockopt(%d, IPPROTO_TCP, TCP_EVENSEG) -> %s\n", s, (*(int *)optval) ? "on" : "off"));
                    break;
            } /* switch */
            break;
    } /* switch */

    sock_set_errno(sock, err);
    return err ? -1 : 0;
}

#ifdef FULL_LWIP
int lwip_ioctl(int s, long cmd, void *argp)
{
    struct lwip_socket *sock = get_socket(s);

    if (!sock) {
        set_errno(EBADF);
        return -1;
    }

    switch (cmd) {
        case FIONREAD:
            if (!argp) {
                sock_set_errno(sock, EINVAL);
                return -1;
            }

            SYS_ARCH_GET(sock->conn->recv_avail, *((u16_t *)argp));

            LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_ioctl(%d, FIONREAD, %p) = %u\n", s, argp, *((u16_t *)argp)));
            sock_set_errno(sock, 0);
            return 0;

        case FIONBIO:
            if (argp && *(u32_t *)argp)
                sock->flags |= O_NONBLOCK;
            else
                sock->flags &= ~O_NONBLOCK;
            LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_ioctl(%d, FIONBIO, %d)\n", s, !!(sock->flags & O_NONBLOCK)));
            sock_set_errno(sock, 0);
            return 0;

        default:
            LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_ioctl(%d, UNIMPL: 0x%lx, %p)\n", s, cmd, argp));
            sock_set_errno(sock, ENOSYS); /* not yet implemented */
            return -1;
    }
}
#endif
